1
In fluid mosaic model of plasma membrane
- Phospholipids form a bimolecular layer in middle part
- Upper layer is non-polar and hydrophilic
- Proteins form a middle layer
- Polar layer is hydrophobic
Answer
(1) Phospholipids form a bimolecular layer in middle part
Solution
As per NCERT, the cell membrane is mainly composed of lipids arranged in a bilayer, with the polar heads towards the outer sides and the hydrophobic tails towards the inner part.
⇒ In the fluid mosaic model (Singer and Nicolson, 1972), this phospholipid bilayer forms the middle (basic) part of the membrane, and proteins are embedded in it (integral) or lie on its surfaces (peripheral).
∴ Proteins do not form a middle layer, and the polar heads are hydrophilic while the non-polar tails are hydrophobic.
Answer: (1)
AIPMT 2002